Page 9 - Journal of Structural Heart Disease Volume 1, Issue 3

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Original Scientific Article
Figure 4: The Lotus Valve System . The bioprosthetic aortic valve implant comprises three bovine pericardial leaflets supported on a braided nitinol frame, and an outer adaptive seal designed to minimize PV-AR.
ery catheter (Medtronic, Minneapolis, MN, USA) fea- tures a complete redesign of the AccuTrak system (Medtronic, Minneapolis, MN, USA) that is currently employed for CoreValve implantation. The EnVeo R catheter with InLine sheath (Medtronic, Minneapo- lis, MN, USA) is a 14 Fr-equivalent system that can deliver the transcatheter heart valve without the requirement for a separate introducer sheath. The modified valve capsule allows the valve to be fully recaptured and repositioned during deployment. The valve is available in 23, 26 and 29 mm sizes. A report of the initial results of implantation of this de- vice in 60 patients revealed no case of mortality at 30-days and 3.4% of moderate or higher PV-AR [20]. As of June 2015 Evolut R has a U.S. FDA approval.
Currently ongoing trials with Evolute R valve are the Medtronic CoreValve Evolute R CE mark clinical study (ClinicalTrials.gov Identifier: NCT01876420) and the Medtronic CoreValve Evolute R U.S. clinical study (NCT02207569).
Boston Scientific Lotus
The Lotus Valve System (Boston Scientific, Natick, MA, USA) comprises a bioprosthetic aortic valve im-
plant and a catheter-based delivery system for intro- duction and delivery of the valve implant [21]. The bioprosthetic aortic valve implant comprises three bovine pericardial leaflets supported on a braided nitinol frame (Figure 4). An outer adaptive seal is designed to minimize PV-AR. Currently, the valve is available in 23- and 27-mm sizes; an additional valve size of 25 mm is anticipated. The transfemoral deliv- ery system is 18 Fr compatible. The delivery handle in- corporates a simple, ergonomic design that enables a controlled, predictable, and accurate deployment. If the initial deployment is suboptimal, the device can be subtly advanced or retracted as needed or even completely retracted into the delivery sheath at any time prior to the final release. The valve functions ear- ly in deployment, providing hemodynamic stability for the patient and enabling the operator to com- plete the delivery process in a controlled and consid- ered fashion.
The multicenter REPRISE II study has been recent- ly published [22]. It examined transfemoral implan- tation of 23- or 27-mm Lotus valve in 120 patients with severe AS. The valve was successfully implanted in all patients, with no cases of valve embolization or additional valve implantation. All repositioning (n= 26) and retrieval (n=6) attempts were successful; 34 patients (28.6%) received a permanent pacemaker. The Mean gradient improved from 46.4± 15 mm Hg to 11.5±5.2 mm Hg. At 30 days, the mortality rate was 4.2%, and the rate of disabling stroke was 1.7%; one patient had moderate PV-AR, whereas none had se- vere PV-AR. CE mark approval for Lotus valve system was obtained in 2013.
Four clinical trials evaluating efficacy and safety of Lotus valve implantation are currently ongoing (Clin- icalTrials.gov Identifier: NCT02202434, NCT02031302, NCT01627691, NCT01383720).
Direct Flow Medical Valve
The Direct Flow Medical aortic valve (Direct Flow Medical, Santa Rosa, CA, USA) is a nonmetal- lic percutaneous valve with an inflatable ring cuff frame designed to encircle and capture the native valve annulus, thereby ensuring anchoring of the bioprosthesis and minimizing potential PV-AR, dis- lodgement or migration [23] (Figure 5). The tricuspid bovine pericardial valve is attached to a polyester
Abramowitz, Y. et al.
TAVR Devices